


Powerpuff Aliens Z! (AMMC #1)

by SonnieCelanna



Series: Midoriya Multiverse - Cross [1]
Category: Ben 10 Series, Demashitaa! Powerpuff Girls Z, 僕のヒーローアカデミア | Boku no Hero Academia | My Hero Academia
Genre: Alternate Universes, BAMF Midoriya Izuku, Ben 10 Classic, Black Z-Rays, Crossover, Cute Midoriya Izuku, Midoriya Izuku Has One for All Quirk, Midoriya Izuku Has White Z-Rays, Midoriya Izuku has the Omnitrix, Midoriya Izuku is So Done, Midoriya Izuku is a Dork, Midoriya Izuku is a Good Person, Midoriya Izuku is a Little Shit, Midoriya Izuku is a Nerd, Midoriya Izuku is a Ray of Sunshine, Midoriya Izuku is a Tease, Multiverse, Omnitrix, Post-Hero Killer Stain Arc (My Hero Academia), Powerpuff Girls References, Pre-U.A. (My Hero Academia), Vigilante Midoriya Izuku
Language: English
Status: In-Progress
Published: 2021-03-17
Updated: 2021-03-17
Packaged: 2021-03-26 15:55:21
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,478
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/30108411
Author URL: https://archiveofourown.org/users/SonnieCelanna/pseuds/SonnieCelanna
Summary: “Black Z-Rays. Mysterious lights we don’t know anything about. All that’s known about black Z-Rays is that they are drawn to negative emotions, and make people powerful, but worse. The best we can do is repel them, let the people hit by them be saved. Stop their powers from going out of control. Probably help them get to therapy as well, to resolve their issues.”“You know, most of that made sense… Although I don’t think my aliens can really take therapy.” A being made of pure green coloured magma said. Izuku Midoriya.To his side, a boy with curly forest green hair, freckles, vibrant emerald eyes and a small smile chuckled slightly at his wisecrack. He wore an odd outfit; a short yellow varsity jacket and a bright green skirt. Also Izuku Midoriya.“I guess you’re right.” The skirt-clad Midoriya chuckled, taking on a fighting stance. He took a breath. “Game faces on, this one’s going to be a dozy. Ready, Watch?”“Ready, Skirt. The bigger they are…”They both rushed forward into the fray.“The harder they fall!”(Fic Crossover. Previous reading not required.)
Relationships: Midoriya Izuku & Midoriya Izuku, Midoriya Izuku & Original Character(s)
Series: Midoriya Multiverse - Cross [1]
Series URL: https://archiveofourown.org/series/2215542
Comments: 1
Kudos: 8





	Powerpuff Aliens Z! (AMMC #1)

**Author's Note:**

> IMPORTANT NOTE: This story is a crossover of "Deku, The Multi-Alien Hero" and "Powerpuff Girl Z: Izuku", previous reading of either is not required but will help in understanding certain details. Set during Chapter Five of "Powerpuff Girl Z: Izuku" and Chapter 42 of "Deku, The Multi-Alien Hero"
> 
> Please enjoy!

“Black Z-Rays. Mysterious lights we don’t know the origins of, the workings of or even why they exist. All that’s known about black Z-Rays is that they are drawn to negative emotions, almost like they feed on it.

They find those who are suffering or confused, those that they are being drawn to and hit them. Change them. Making them stronger, but more unstable. A strongman discovers his wife is cheating on him? Now he’ll be able to punch buildings to dust, but all he’ll want to do is use that strength against the people who hurt him. That kind of thing.

There is no known way to contain them yet. All we know is how to make them be repelled, that’s the best that can be managed for now. Let the people hit by them be saved, stopping their powers from going out of control. Probably help them get to therapy, to resolve their issues.”

….

“You know, most of that made sense… Although I don’t think my aliens can really take therapy.” A being made of pure green coloured magma and a few red rocks floating atop hummed, bright white eyes glowing where there would be a face. Upon his chest, a green and black hourglass symbol on a circular plate was present. His ‘hair’ was like a form of green flowing fire, emulating a long, flowing mane of all things. His name was Izuku Midoriya.

To his side, a boy with curly forest green hair, freckles, vibrant emerald eyes and a small smile chuckled slightly at his wisecrack. He wore an odd outfit; a short yellow varsity jacket with green trims and a large bubble writing P on the right side, black fingerless gloves, a black choker with another P on it and green diamond hair clips. He also had bulky white bangles and anklets with green stripes going all around the centre, green shoes with large white soles and a ring with a green top and yet another P on it. Finally, the main part of his outfit looked like a green dress with black trims from afar however upon closer inspect one could see that the skirt and the main body piece were separate, held together by a white belt with a large green button with one more P on it that could be detached if the boy wanted. His name was  _ also _ Izuku Midoriya.

“I guess you’re right.” The skirt-clad Midoriya chuckled, taking on a fighting stance. He took a deep breath. “Game faces on, this one’s going to be a dozy. Ready, Watch?”

“Ready, Skirt.” The fiery Midoriya nodded, taking on a similar fighting stance as his fires flared. They both looked up to their shared enemy. Five giants, towering two-hundred-foot tall, imposing and storming through the waters of Dagobah to destroy the city, dark hateful auras surrounding every single one. “The bigger they are…”

They both rushed forward into the fray.

“The harder they fall!”

* * *

_ Earlier that day _

Two weeks before the Entrance Exam at U.A. High School, Izuku Midoriya (currently in disguise as the new vigilante of Musutafu, Z-Ray) had found himself chasing yet another black Z-Ray-infused villain, a black haired man with a faux hawk haircut, black faded jeans, a tight fitting leather bike jacket and grey sneakers with white soles and laces.

One that had taken to calling himself Respawn, a name he’d chosen because he possessed a quirk to duplicate items. A cool if somewhat simple quirk on its but with the black Z-Rays that had hit him he’d been giving Izuku quite a bit of trouble as he made his escape.

One football thrown at him was easy to avoid, a hundred at once was a nightmare even if it didn’t really hurt thanks to his super durability. After all, no amount of super speed would allow him to phase through a massive solid wall of balls.

Still, with the fact he had nothing but duplication on his side, Izuku was able to eventually catch up to the much slower villain, driving a literal flying kick into their back, knocking them down into the street.

Yeah, he was definitely far from the most troublesome villain the green haired vigilante had faced. Between Astral Portals, self-proclaimed “Time Goddesses” and more, duplication was low on the list of troublesome things he’d had to deal with.

They hit the ground, rolling across it as Izuku landed atop the villain, glad today wasn’t going to be a long day as he stopped the black haired man and began repelling the black Z-Rays from their body, holding his hands out and channelling all the white Z-Ray energy inside through him, to make the black Z-Rays retreat.

Respawn tried to fight back, pushing a hand up into an attempted punch that Izuku lazily dodged, grabbing it and holding him down. ‘Almost there-‘

And that’s when things went weird. When things went wrong. The blue cloudy sky above turned dark. There was a rattling in the air, as if the very atmosphere around them was shuddering under some new weight. Things felt off, wrong, slow…

Something wasn’t right.

CRACK!

Izuku’s eyes went wide as both he and Respawn turned confused, only to see the window nearby suddenly shatter before a large black creature came flying out, rolling across the ground as he crackled with green electricity. Then in a sudden green flash, he changed and all that was left in his place was-

Was Izuku’s body? In some sort of green heroic jumpsuit costume thing? What the hell?!

A sudden crackling noise got his attention as Respawn tried to throw his arms away and suddenly the black Z-Rays exploded out, while at the same moment there was a massive green light to the side, the wrist of the lookalike lighting up before all sorts of massive weird shapes and creatures went hurtling out making Izuku go wide eyed as the lights hit him.

Then a moment later it was over. How did he react? How did he…

“Ugh… my head… Sorry Gwen- Gwen?” He heard his voice as the lookalike pushed himself up, before turning to the skirted Midoriya. He froze in confusion, his eyes narrowing. Then they hardened into a glare. “HEY! GET AWAY FROM HIM!”

Then it hit Izuku, a duplicator! He was fighting a duplicator! Did he clone him?! He stood up into a fighting position in preparation, when he saw it. The lookalike threw his hand down, trying to hit something on his wrist.

He wasn’t sure why, but he was pretty sure it was a lead in to an attack and he couldn’t let that happen! So he rushed forward as fast his speed could carry, which meant he was across the street in practically a second as he threw a punch forward into the new green flash that had engulfed his look alike.

His punch missed and he turned to see a giant, anthropomorphic bipedal muscular tiger that let out a snarl and threw a fist forward a spike on the end of his fist.

Izuku reacted quickly, throwing his arms to block the punch and the creature hissed, backing off and shaking his hand as Izuku blinked confused. Then he experienced something he usually only experienced with Kacchan. Immense confusion as an incredibly angry animal yelled in his face.

“ARRRGH! RATH’S HAND HURTS!” He roared before turning with a feral look, putting up an accusing finger with a snarl. “LET ME TELL YOU SOMETHING, SKIRT MAN! RATH DOES NOT APPRECIATE YOU BEING TOO SOLID TO HIT! RATH IS GOING TO HIT YOU HARDER FOR THAT!”

“What- Crap!” He blocked just in time again, making the tiger howl once more before he changed tactics, dropping down and grabbing the skirt wearing vigilante’s leg, picking him up with ease and spinning him around, throwing him away but not before Izuku hit his fist, forcing it open before he began flipping backwards through the air.

He went into a proper flight with a groan and glared, rushing back in as he formed a massive mallet the size of himself in his hand. “I don’t think so, kitten clone!” 

“LET ME TELL YOU SOMETHING, CROSSDRESSING GUY WHOSE GOING TO BEAT RATH WITH A HAMMER! RATH DOES NOT APPRECIATE BEING CALLED KITTEN OR A CLONE!” The tiger alien roared as he rushed forward as well, sticking his jaw out at the last moment as Izuku went for a swing, sinking his jaws into the wood and snapping in half.

Izuku froze.

“What- OOF!” He took a proper blow to the stomach, his defense dropped in his shock before he was slammed into the ground once, twice and then thrown into the wall. “Argh! Enough, I’m not gonna let some duplicate let the bad guys get the way!”

  
  


“RATH ISN’T A DUPLICATE! SKIRT MAN IS A WEIRDO! WE LOOK NOTHING ALIKE!” He roared once more, however he’d stopped moving. Izuku blinked.

“But… I was fighting a cloner. You have to be a clone. You looked just like me before I transformed.” He said, more quietly, his mind racing as he tried to think. But… he’d panicked and not really had a chance to think, to question why the hell he was so different.

After all, last he checked he couldn’t turn into a giant angry tiger. (Although. considering his powers unpredictability, he wouldn’t be surprised if it was a possibility.) What other explanation could there be though?

“Rath looks nothing like you! Nor does Rath’s human form!” He raised his hand and tapped the symbol on his chest that Izuku had failed to notice before three times, yet another green flash engulfing him and then there before him the clone stood. His own voice spoke to him. “See? Green hair? Freckles? Don’t look anything like you. I don’t have blue hair or purple skin.”

The skirt wearing Midoriya blinked before he remembered one of his powers. “Oh right, identity concealment. Uh… Nice to meet you, my name is Izuku Midoriya.”

“No I’m- What the-“ His counterpart jumped, before narrowing his eyes and looking him up and down. “...What?”

“Surprise?” he chuckled somewhat nervously before floating down, landing on his feet and looking up. “You’re not a clone?”

“No! You’re not either?” He asked confused and Izuku- fuck this was gonna get confusing.  _ Z-Ray _ shook his head. He blinked before going wide eyed. “Wait then was that a- Shoot!”

Z-Ray turned as well and sighed as he realized that Respawn had got away. “…Yes, that was a villain if that’s what you were about to ask.”

“Oh no…” The confusing counterpart paled as he put his hands to his face, groaning. “Crap, sorry! I just, I saw you over him and it looked so much like a mugging or something.”

“No, I can see that.” Z-Ray shook his head, turning to him with a sigh. “I shouldn’t have rushed you anyways without trying to explain, I thought you were going for an attack and rushed in.”

“Ah, right…”

“It's fine anyways.” Z-Ray said, a hint of relief in his voice as he looked around. “The thing that was making him all nuts and an overpowered issue is more or less gone anyways. There’s maybe like a little tiny bit of residue I didn’t get but it’s probably negligible. So uh… who exactly are you?”

“Who are  _ you? _ ….” He looked Z-Ray up and down before wrinkling his nose. “And what the heck are you wearing? Did Ashido make you wear this?”

“Who?”

“…Ashido?” He repeated, only to get a blank stare from Z-Ray. “Pink skin, black sclera, horns, would find pranking us into wearing that hilarious so as long we weren’t too upset by it?”

“...Never heard of her.” Z-Ray shrugged, and it was true. Seriously, what was an Ashido? “And this is a side-effect of my powers.”

“…Excuse me?”

“If you’re going to call bullcrap, trust me I wanted too as well.” Z-Ray deadpanned, crossing his arms. “And while we’re speaking of powers, the heck was that tiger thing?”

“An alien.” He said simply, holding up his wrist to show a black and green watch. The skirted Midoriya blinked slowly.

“…And I thought my life was a drug trip normally.” He eventually said after a moment. His counterpart shrugged and sighed, tapping the watch.

“Okay, let’s start from the beginning. First, just so we can be perfectly sure on both sides this isn’t a trick, early memories. When we were young, who was our favourite hero?” The counterpart asked and Z-Ray sighed again, this one was way too easy.

“All Might and he still is now.” He said, before fixing the other with a glare. “The song mom put on all the time to cheer us up when we got sad.”

“Special, by Shinedown. If that didn’t work, she’d put on Get Up, same band.” The counterpart guessed immediately. He sighed with a blush. “One more…. Mom’s…. Mom’s nickname for us when we were five.”

Z-Ray went nuclear as he gritted his teeth and looked away, unable to say it with any dignity. “….L-Little sugarlump cause we dumped s-sugar all over ourselves by accident.”

His counterpart, blushing just as bad, nodded as he sat down on the curb. “Alright, alright. I have a theory then… Did you go through the day where the Slime Villain attacked?”

“Usual high school bullies, Kacchan goes too far with suicide baiting, nearly choke in slime, All Might saves the day, ruins the day, Bakugou nearly drowns, then we’re offered the strongest quirk on the planet. Kinda hard to forget.” Z-Ray hummed, taking a seat beside his counterpart. “Three months later and I end up like this.”

“Three months for you too, huh? For me, All Might decided we could have a break for just one day. Still had to do some training, but he took me out to camp, so that I at least had something other than cramps to take away from it all in the early stages. Did he do that with you?” The jumpsuit clad Midoriya inquired, raising a brow. Z-Ray shook his head as he let out a low whistle.

“Lucky, and no he didn’t. Three months in and we were walking home from the usual day of struggling on the beach and slight hazing. Not mean spirited, just All Might trying to be motivational I think. We’re walking home and I see these lights falling out of the sky. Three bright white ones and they were going to hit these kids who were out playing. I didn’t think, I just knew they were at risk and All Might didn’t have time to change, so I dived in the way.” He gestured over himself with a slight huff of a laugh. “Next thing I know I’m holding a hammer, wearing a skirt and flying.”

“...I’d say that’s hard to believe but my story isn’t all that different honestly.” His counterpart chuckled quietly as he scratched his neck, looking down. “I went for a walk to clear my head, saw a light come crashing down, fell down a cliff face and found what I thought was the crash site of a meteor. Instead it was some kind of container. It opens up and next thing I know…” He held up his wrist, showing Z-Ray the watch. “The Omnitrix latched onto my wrist.”

“Omnitrix?”

“Yeah, that’s what everyone else calls it. Honestly All Might’s alien theory was just some crazy speak at first, but then I got into U.A., got abducted, just saved an entire illegally imprisoned group of aliens twenty minutes ago, basically it became a lot more plausible that they could be aliens, the forms the watch let me transform into. What about you? You clearly transform and… even if the uh, fashion is questionable there’s got to be something worth it to it. You were pretty sturdy.” Omni, as Z-Ray had mentally dubbed him thanks to the watch, said as he looked him up and down. “And you were flying.”

“Super durability and flight.” Z-Ray nodded, humming. “Energy tracing, heat vision, super speed and super strength. Oh and yeah, summoning that hammer and a super soaker at will.”

“...That last one is so random that I’m not even gonna question it.” Omni decided, shaking his head.

“Yeah- Wait, you're in U.A.!” Z-Ray suddenly realized what he’d actually been told as he went wide eyed in shock. Omni blinked before chuckling as Z-Ray practically got right up in his face. “What’s it like!? Is it cool?! How hard is it to get in-“

“Calm down!” He shouted, putting a hand to his chest and laughing nervously. “God is this what we’re like usually? I should apologize to Yaomomo and All Might when I get back… Yes U.A.’s cool, super cool, and it’s hard to get into but if I got in I’m sure you can as well.”

“Right!” Z-Ray beamed, his hesitance replaced by excitement. “So you had a theory?”

“Ah, yeah. See, I was working with someone just before I came here to recover an artefact. An artefact they said could let people go through dimensions, or more accurately to alternate realities. Alternate universes.” He explained and Z-Ray stopped, before going as wide eyed as he could at the implications. “I hit it with a blast by accident and then I ended up here.

“….Oh. Oh crap.” Was all Z-Ray could think to react with, getting a nod in response.

“Yeeeep.” Omni sighed, rubbing the back of his head. “That long freeing and scanning new aliens and then I get thrown into a whole new world. This is definitely going up there as the most complicated thing that’s happened to me so far.”

“Dang. All I’ve done is take down a few overcharged villains…” Z-Ray winced, feeling pretty out of his depth all of a sudden. However, a thought hit him and he looked up. “There was an explosion from your watch by the way, when you first arrived. I saw all these silhouettes. The things I’ve been trying to stop hit them. Do you have any idea what that was?”

He blinked confused before pulling up his watch, pulling up the faceplate and twisting it, going through his list. His face slowly paled. “…Some of my forms are missing. The aliens that should be in here aren’t!”

BEEP! BEEP! BEEP!

They both blinked and looked down, seeing the giant green part of Z-Rays belt was beeping and flashing. He pulled it out the clip, flipping it open to reveal it was actually a miniature communicator of sorts, looking at the screen and cursing. “Found your aliens.”

“What-“ Omni came over and went wide eyed as he saw the same thing Z-Ray did on the screen. It looked like mutants to Z-Ray but aliens to Omni, his aliens, wreaking havoc with way more power than they should have had. “No, no, no… Pyroform, Reverb, Cannonshot, Chiller… Wait, Goliath?! How in the world did he sneak away?”

Z-Ray grunted. Around every single one, he could see a dark aura surrounding them. Black Z-Rays. “They’ve been enhanced as well. I’m going to have to get those rays out of them.”

“Guess we’ve gotta team up then?” Omni asked, looking up sheepishly. “Cause I need them back in the Omnitrix.”

“Looks like it.” Z-Ray nodded, flicking the communicator to lead them to the closest one. “Come on, the round rolling one is this way!”

“Cannonshot.” Omni supplied as he followed, both hurrying their pace down the street. “Oh yeah and uh… what do I call you? Cause Izuku is just gonna be weird.”

“Well… I’ve been calling myself Z-Ray as a vigilante name.” He suggested and Omni hummed for a moment in thought.

“Z-Ray huh? Cool, maybe slightly tacky.” He paused before getting a grin Z-Ray didn’t trust. “Actually, seeing as you technically attacked me first, I’ve decided for my compensation I’m going to call you skirt.”

“Of course you are.” Z-Ray groaned, not knowing how anyone put up with himself. “And for that, Watch, we’re going the hard way.”

“Wait wha-“

Z-Ray grabbed his counterpart by the shirt and flew them up at speed, ignoring his surprised shouts as he blasted off towards where the alien was causing trouble.

Neither had noticed, behind a corner breathing heavily and glowering at their retreating forms was Respawn, looking down at his hands. The darkness was growing again.

He turned to a woman walking nearby, who was frozen completely solid, unmoving, just like the sun past the darkened sky. He pushed her. She didn’t move at all. That was weird but didn’t matter, as he turned to rush off to find something more important.

An unsettling grin spread over his face as he made sure he could still feel his quirk. He had a plan to get back at that bastard Z-Ray…


End file.
